Previously proposed is a walking assistance device that includes a power generator such as an electric motor to apply a working assistance force to a lower limb of a user for the purposes of assisting the walking movement of the user, and/or rehabilitating the walking impairment of the user by helping the user to regain the motor coordination that is required for the user to walk. See patent document 1 (Japanese patent laid-open publication JP2006-320349A), patent document 2 (Japanese patent laid-open publication JP2006-320350A), and patent document 3 (Japanese patent laid-open publication JP2007-152035A).
Such a walking assistance device typically includes a pelvic support assembly consisting of a C-shaped main frame configured to be worn on a pelvic part of the user and extending from a lower back part of the user to either side of the pelvic part of the user and an abdominal belt for securing the main frame to the pelvic part of the user, a pair of power generators mounted on either lateral end of the main frame (at parts corresponding to the hip joints of the user) and a pair of femoral support assemblies for transmitting the power generated by the power generators to the corresponding femoral parts of the user.
A previously proposed femoral support assembly includes an arm member or a swing arm consisting of an elongated flat bar member made of a relative stiff material. The swing arm includes a base end attached to the output end of the corresponding power generator, a free end located on the front side of a lower femoral part of the user and an intermediate part extending between the base end to the free end of the swing arm along the outer contour of the femoral part of the user. Therefore, the swing arm is twisted by about 90 degrees as it extends from the base end to the free end. The free end is fitted with a flexible belt passed around the lower femoral part of the user in a releasable manner. See patent document 4 (Japanese patent laid-open publication JP2009-95645A), for instance.
The femoral support assembly for a walking assistance device is required to be able to apply the power generated by the power generator to the femoral part of the user in a reliable manner on the one hand, and to fit favorable onto the body of the user without causing discomfort or stress to the user.